diff --git a/blockdiag/requirements.txt b/blockdiag/requirements.txt
index 416151ec6..2ed96a699 100644
--- a/blockdiag/requirements.txt
+++ b/blockdiag/requirements.txt
@@ -4,7 +4,7 @@ Click==7.1.2
 Flask==1.1.2
 funcparserlib==0.3.6
 gunicorn==20.1.0
-itsdangerous==1.1.0
+itsdangerous==2.0.1
 Jinja2==2.11.3
 MarkupSafe==1.1.1
 nwdiag==2.0.0